Precision vise of the double-acting type



May 25, 1954 F. G. GEPFERT PRECISION vIsE 0E THE DOUBLE-ACTING TYPE 3Sheets-Sheet 1 Filed May 13, 1953 d d a .E .d n u E z 7 .m/ lien.' 7 M ML w 5 Ill. 5 7 n |||s Z l 1.. 1 1 74 E E... 4 9 r/. 8 6. r3 7 [I \e. 8 8wald-I7 2 3 xl 7 B 9 G a a E u May 25, 1954 F. G. GEPFERT 2,679,177

PRECISION VISE OF THE DOUBLE-ACTING TYPE Filed May 13, 1953 3Sheets-Sheet 2 9a 13K a4 4a 1 zaL z 4a 4c, 318415 7 6.

31 11. Qa -ra 69 zo 3Q, 24 51 49 z8 zv s4 sa s4 sa, 3a 21 -n May 25,1954 F. G. GEPFERT 2,679,177

PRECISION VISE OF THE DOUBLE-ACTING TYPE Filed May 13, 1953 3Sheets-Sheet 3 INVENToR. PANA/nv Gf GEFA-5er /0' 12x/@Mi unw'm ,l

MMIMW Patented May 25,v 195.4

UNITED STATES PTENT QFFICE PRECISION visE oF THE DOUBLE-ACTING TYPEFranklin Gah! Gepfert, Cleveland, Ohio Application May 13, 1953, SerialNo. 354,849

9 Claims.

This invention relates to a precision vise of the double-acting typeand, in particular, to a vise of this kind in which the jaws are moved'oy iiuid pressure motors.

It has been known heretofore that under sorne circumstances one or bothof the jaws of a vise may be moved by means off iiuid pressure, butprior vises of these types have not so fear as known aiorded theadvantages that result from having two `fluid pressure motors inalignment with the jaws of .the vise, particularly with the jaws vsoarranged as to act in synchronisrn with each other. According to thepresent invention, a pressure fluid from e common .Source is suppliedsimultaneously to two fluid pressure motors of the nature of powercylinders provided with pis.- tons and piston rods on which the JaWs ofthe vise are mounted. By aligning the jaws with the power cylinders inthis manner, unnecessary power losses and leakage of pressure fluid canbe precluded. At the saine time, the synchronizing mechanism, whichforms part of the preferred embodiment `of the present invention,lserves to maintain the jaws in the desired relation to .each other andto the base of the vise regardless of Whether the jaws are in openposition, in closed position, or in any intermediate position.

One Aof the objects of the invention, therefore, is to provide a vise ofthe type described in which two aligned uid pressure motors koperatedirectly on the jaws of the vise with the intervention of only Lsuchindispensible connecting elements as pistonrods, couplings, etc. Anotherobject of the invention is to provide a vise of this kind in which the.work piece may be located in the vise within a tolerance, plus orminus, of about .001 inch of the intended center. Another object of theinvention is to provide a precision vise of this kind in which either orboth of the jaws may be adjusted to accommodate unsymrnetrical workpieces, this without sacrifices ci the advantages that inure from thedirect application voi the motive `force to the jaws ofthe vise. Stillanother object vof the invention is to provide a precision vise of .thiskind in which relatively high clamp.- ing forces may be obtained, as,yfor example, clamping forces up to and above 2000 pounds. Stillantherobject-of the invention is Ito provide novel `ways and means forguiding the j aws over the platform and along the sides of the haseforming part ofthe vise.

Other objects and advantages of the .invention will .be apparent tramitedescription which r fellows and from the -ecempanyine drawings ,1n

which Figure l is a side elevation of the vise in open position, thepressure fluid lines being omitted in the interests of clarity.

Figure 2 isa corresponding central vertical section through thelongitudinal axis of the vise, the false jaws shown in Figure 1 beingomitted'.

Figure 3 is a top plan corresponding'generally to Figure 1 but showingthe jaws in closed position.

Figure 4 is a top plan corresponding generally to Figure 2.

Figure 5 is a bottom plan corresponding to Figures 2 and li but showingthe pressure fluid lines.

Figure 6 is a transverse vertical section on lines -Gof Figures -2 and4. A

Figure '7 is a transverse vertical section on line 1-1 of Figure 4.

Figure 8 is a front elevation showing the forward face of the innercylinder head.

Figure 9 is a corresponding side elevation.

Figure 10 is an elevation of the outer cylinder head and hase as seenyfrom the rear of the vise; i. e., from line IIJ-i0 of Figures. v A 'YFigure 11 is a fragmentary section through part of the outer cylinderyhead on line H-H lof Figure 5.

Figures i to '7 are on a much reduced scale; Figures 8 to 11, on asomewhat llarger' scale 'out less than iull scale. l Y 'Y 4 The viseshown in the drawings includes an obiong ylease l best seen in Figuresl, 2 and 5. it incorporates a slotted platform 2 at the ends of whichare mounted two fluid pressure motors@ and k4, the same taking the forrnoi Dpower cylinders. Within the power cylinders are the pistons ii and(i, to which lare respectively connected piston gods 'l and ii. At theforward end s'of'the piston rods 1 land y8 lare the master jaws Si andl0, on which rnay be rnounted false jaws I l and l2 respectively.Connected to master jaws e and l!) are two raeksi and i4 (Figure 5*),one on each side of the vise. Located between racks it and lli andco-.operating with them is a stepped gear ri5 mounted for rotation on acap screw the cap I7 of .winch hears against the narrow lower face l5@of the gear l5 and the threaded upper end I8 of .which is screwed intoplatforin A2. `See Figures 2 and 6. A set screw i9 tapped access openinglila y(Figure) voperates on threaded portion I B to holdcap screw it inplage.

As yappears from Figure 5, base i lis characterized .by the twosymmetricalend portions 2t and 2| from .which .longitudinally extendinglcentral webs `222 and 2 5, respectively, `project toward centero thevise. Each of the two central webs 3 22 and 23 is anked by a short webon one side and a long web on the other, the short webs being designated24 and 25 and the long webs being designated 2S and 2l. As further shownby Figure 5, short web 2li is in alignment with long web 2i; short web25, with long web 2B. Between them on opposite sides of the vise areformed the open areas indicated at 2S and 2S in Figures 4 and 5, suchopen areas being provided to accommodate hereinafter described portionsof master iaws s and lil. As previously mentioned, platform 2 isSlotted; as shown in Figure li, it has two longitudinally extendingmachine-nished slots 3G and iii, one on each side of the longitudinalaxis of the vise.

Along the long edges of slots 36 and Si the lower face of platform 2 ismachined to provide recessed guideways (Figure 5) which guidewaysparallel slots 3l] and 3l throughout the lengths of the slots. Asindicated in Figure 7, slot t is flanged by recessed guideways 32 and33; slot Si by recessed guideways E6 and 35. Co-operating with guideways32 and and guideways 3e and '55, respectively, are slideable keys 31 and36, best seen in Figure '7, which keys are machined to nt accuratelyinto the slots and guideways. Screws 38 and 39 hold the keys to masterjaw S, while similar screws hold two like keys to master jaw le. Thekeys are T-shaped in transverse crosssection, their Shanks projectingupward through the slots and their heads bearing against the re cessedguideways that flank the slots. The threaded ends of screws iid and 39are received in tapped openings in overlying portions of master jaws land le.

As appears from Figures l, 4 and '7, master jaws 9 and le arerespectively characterized by horizontally extending portions d5 andlle, such horizontally extending portions l5 and l projecting rearwardlyfrom vertically extending portions 41 and de to which false jaws Il andi2 are applied as shown in Figure 3. The lower surfaces oflongitudinally extending portions 45 and 46 and vertically extendingportions 47 and 48 are machined to facilitate smooth movement of masterjaws Si and le across the machined upper face of platform 2. Master jaws9 and il! are further characterized by dependingportions i9 and E0, seenin Figures l and 6, which lportions, depend below the level of platform2 into the open areas 23 and E@ along the sides of the vise. Depending I-portion t9, seen in Figure l, is integral with horizontally extendingportion d5 and vertically extending portion el of master jaw 9;similarly, depending portion 59, seen at the left in Figure 6, isintegral with horizontally extending portion iii and verticallyextending portion 128 or" rmaster jaw it. Depending portion le is on thenear side and depending portion 5e on the far side of the vise as seenin Figure l.

Rack it is held in horizontal relation to depending portion 4S of masterjaw 9 by screws 5l (Figure 5) similarly, rack lll is held in horizontalrelation to depending portion 5i) or" master jaw lli by screws 52. Theprojecting portions of racks i3 and lli are machined and extendforwardly into contact with machined inner surfaces i and 53 on longwebs 2l and 2S, respectively, such inner surfaces acting as guides forthe racks in the manner indicated in Figure 6. As in the case o1c theupper face of the platform and the contacting portions of the masterjaws, the webs and racks are preferably machined to close tolerances tofacilitate smooth movement of racks i3 and lli toward and from Webs 2land 26.

The vertical portions il and i8 of master jaws 9 and i@ are provided asshown in Figures l and 2 with horizontally extending slots and, as shownin Figure 3, with vertically extending slots 56. The horizontally andvertically extending slots intersect as shown in Figure 6. To the rearof horizontally extending slots 55, master jaws le and il are drilled asindicated at 57a in Figures i and 6 to provide passages to accommodatethe cap screws 5l that are employed to hold false jaws il and l2 inplace. Cap screws 5l appear in Figures 1 and 3. They extend fromopenings Sib at the rear of vertically extending` portions il and i8into passages Ela and thence into tapped openings in false jaws il andi2. rl'he relationship between cap screws 5l, master jaws 9 and lli andfalse jaws li and i2 is best seen in Figure 3.

Extending rearwardly from vertically extending portions il and iS ofmaster jaws 9 and i@ are the integral hub-like projections 58 and Si)which are provided to accommodate the threaded portions @il and el ofpiston rods l and 8. Lock nuts 52 and metal washers t3 (Figure 2) areprovided to keep master jaws 9 and lil from working loose from pistonrods 'i and 8. A stop collar ed taking the form of a clamping ring ismounted on piston rod 8 as shown in Figures 2, 3 and 4. Stop collar515.- is held in place by a clamping screw 55. If such a stop collar isprovided. on either of the two piston rods, it is unnecessary to providea similar stop collar on the other piston rod if, as in the preferredembodiment oi the invention, the jaws are synchronized with each other.

Fluid pressure motor 3 at the left hand end of the vise as seen inFigure l is made up of an inner cylinder head (il, an outer cylinderhead 53, and a cylinder wall Sie, the latter being mounted in circulargrooves on the inside faces of cylinder heads 6l' and 68. Fluid pressuremotor li at the opposite end of the vise is similarly constructed of aninner cylinder head il), an outer cylinder head il and a cylinder walll2. Stay bolts 'i3 are provided to hold the parts together and are soarranged that their heads Illia are accessible from the ends of thevise. If desired, they may take the form of studs mounted on innercylinder heads 5i and "iii, in which vase heads i1-ia will take the formof nuts threaded onto the outer ends of the studs. By these or similarmeans, fluid pressure motors 3 and e can be held together in a mannerminimizing the possibility of leakage of the pressure fluid. Wherepiston rods l and S pass through inner cylinder heads 6l and le,suitable seals of resilient material are provided as indicated at lilaand lea in Figure 2. Where pistons 5 and e come into contact withcylinder walls S9 and l2, the pistons are provided with conventionalO-ring seals held in suitably formed grooves, this construction or" thepistons being illustrated in Figure 2.

As indicated in Figure 10, the rear face of outer cylinder head 'il hasa tapped central bore 14a for receiving the threaded portion of aconventional metal coupling 'M through which a pressure rluid such ascompressed air or oil under pressure may be supplied from an externalsource (not shown) including a connecting fluid line, a four-way valve,and a tank of the nature of a reservoir. As appears from Figure 8, in-yner cylinder head 'lll is similarly provided with a radially mountedcoupling 'i5 threaded into a tapped opening it communicating with aradial passage 'il extending to a point located interiorly of cylinderwall 12 and there it self communicat-V ing with a 'port l in opencommunication with the space between piston'G and the inner face of'inner cylinder head l0. By means of port 118, passage 1l, opening 'i6and coupling "a5, the pressure fluid may be exhausted from the spacebetween piston 6 and cylinder head 10 during the time when pressurefluid is being supplied to the space on the opposite side of piston 6,thus forcing piston il from right to left as seen in'Figure 2.

When the four-way Valve is reversed, pressure fluid is admitted to fluidpressure motor d through coupling l5 and exhausted from uid pressuremotor 4 through coupling lll, thus forcing piston 6 from left to rightas seen in Figure 2. It this movement of piston 5 that is limited bycontact between stop collar E4 and the forward face of inner cylinderhead lll. Thus the introduction and withdrawal of pressure fluid fromopposite sides of piston @determines the position ofthe piston 5, pistonrod t, and master jaw it.

Similar means, including lcouplings similar to couplings 'M and l5, maybe used in the case of uid pressure motor 3, Abut in the preferredembodiment oi the invention such are not necessary `and therefore arenot shown in the drawings.

VWhereas outer cylinder head 'EI is circular as seen in end elevation,as in Figure 10, inner cylinder head lil has the shape shown in Figures8 and 9. in addition to a central bore 'ES for piston rod '8, cylinderhead le is provided with bores 8i! and 8| for cap screws 82 which, asshown in Figure l, help hold inner cylinder head lll to hase El. Theforward face of inner lcylinder head 'l0 has two forwardly extendingbrackets formed integrally with the cylinder head itself, such bracketsbeing seen in each of Figures 8 and 9. 'Ihey consist of the horizontalprojections 83 and 8G and reinforcing webs S5 `and 8%. As shown inFigures l, 3 and 4, hold-down screws 81 serve 'to locate inner cylinderhead it and hold it firmly in place on base l, to which end forwardlyextending projections 83 and ll are provided With openings accommodatinghold-down screws IS?. Similar hold-down screws t8 are ernployed forinner lcylinder head 1671' of fluid pressure motor '3.

Referring again to Figure 8, which shows the forward face of innercylinder head 10, it will be noted that a port 9| extends inwardly fromthe forward face of cylinder head lil. lort "Qi does not pass completelythrough inner cylinder head .lil but terminates approximately midwaybetween the forward and rear faces thereof. It is in communication witha radial passage s2, plugged Aas at 93 at its outer end, which is itselfin communication with a port 94 that extends rearwardly from radialpassage S2. .Port 9d is in open communication with the Aspace betweenpiston t and the rear or inner face of inner cylinder head '(l. Port SIis tapped as indicated at Sla to accommodate the threaded vportion ofthe external metal coupling 95 shown in Figure 5.

Attached to coupling 95 is a line 96 of copper, brass or the like whichextends longitudinally toward the central Zone of the vise, then curvesaround the edge of the narrow portion l5a of gear i5, and continueslongitudinally toward the Aopposite end of the vise, where vit isreceived in a similar coupling ill at the base of 4inner cylinder head.Sl of fluid pressure motor v3. Cylinder head 6l is provided with a...threaded opening, an .externally plugged vradially extending passageand a port that are respectively similar to opening 9i, passage 92 andport YSill in cylinder head lil. Thus the two fluid pressure motors arein constant communication with each other by means of line Qt, such lineequalizing the pressures obtaining in the spacesbe tween `the pistonsand the inner cylinder heads.

A similar line 99 extends as shown in Figure 5 from a coupling it@mounted at the base of the inner face of outer cylinder head ll to alike coupling I0! mounted at the base cf the inner face of outercylinder head '38. As in the case of line 95, line S9 circles part wayaround gear I5. It crosses line 55 in the manner shown in Figure 5. Line99 is used after the fashion of line B to equalize the pressures whichobtain in the two fluid pressure motors in the spaces between thepistons and the inner faces of the outer cylinder heads. Where line F'is coupled to the outer cylinder head, the latter has a threaded openingH32 extending part way through the cylinder head which threaded opening|02 is in communication with a radial passage ill that is plugged as atitil: see Figures if) and ll.

The construction shown in dotted lines i-n Figure '-16 lin the ease ofouter cylinder head 'i i `of fluid pressure motor l is duplicated inouter cylinder head 63 of iiu'id pressure motor 3. Where line S9 passesthrough inner cylinder head l0, `the latter is provided with an openingits (Figure 8). There is a counterpart opening for lne "lig in innercylinder head Immediately to the rear oi such openings for ine 99, baseAI is provided with similar openings (not shown).

It is the construction just described, making use of crossed lines andd, that maires it possible to dispense with couplings on fluid pressuremotor 3 analagous to couplings 'le and l5 on fluid pressure motor fl.While external con nections to couplings ll and l5 are necessary, theneed for like external connections to fluid pressure motor 3 isobviated. ln lieu thereof, the two fluid pressure motors areinterconnected by lines El and di), the former of which presents less ofa problem than the latter in View of vthe fact that it extends fromcoupling 95 to coupling Sl without having to pass through the base orany of the various cylinder heads. Line 99 of course requires that theend portions of the base and the two inner cylinder heads be providedwith aligned openings at each end of the vise through which line t9 canpass from coupling it to coupling mi.

With the apparatus illustrated in the accompanying drawings, either agaseous or a liquid pressure fluid may be employed, although preferablyit is compressed ail1 under a pressure of from about 5 to about 100 lbs.per square inch. By suitably varying the pressure within these or otherlimits, a force of varying magnitude can be developed in the zone wherethe work piece is grasped by false jaws l l and i2. In a typical case,the piston has a diameter of 31/2 inches exclusive of the O-ring seal,so that clamping forces of magnitudes up to about 200e lbs. may beobtained without difculty. These forces are exerted in such a way thatthe resultants of all forces acting on the two jaws are not only inopposition to but also in perfect alignment with each other.

The incorporation in the assembly as a whole of `gear l5 and racks i3and lll introduces a synchronizing mechanism into the vise. Althoughpreferably present, such synchronizing 'mechanism may be omitted ifdesired. At no time is any clamping pressure transmitted through thesynchronizing mechanism. Its function is to provide uniformity of travelbetween the two extreme positions of the jaws illustrated in Figures 1and 3, in the former of which the jaws are fully open and in the latterof which the jaws are closed together.

Where, as in the described embodiment of the invention, the partsexperiencing relative movement are machined to close tolerances, thecenter of the work piece may be located within plus or minus .001 inchof the established center lines, both horizontally and vertically. Inthe embodiment of the invention shown in the drawings, each jaw isindependently adjustable with relation to such center line, as by meansof lock nuts 62 and washers 63 on threaded portions 60 and 6I of pistonrods 'l and B. Thus the jaws can be readily moved as needed toaccommodate unsymmetrical work pieces. if desired, the same result maybe obtained by using non-identical false jaws in place of the identicalfalse jaws I l and l2.

Thus the vise of the present invention is a precision tool adapted tolocate centers or other predetermined points regardless of the shape orvvarying` size of the work. As a result of the construction of the baseand the manner of mounting the fluid pressure motors, the vise is strongand sturdy. By virtue of the manner in which the jaws are guided on theplatform. lost motion is virtually an absent factor. rlhe close limitsof accuracy required for fine work are met; in consequence, the vise maybe used for such .precision operations as chamiering, countersinking,counterboring, end milling, drilling, tapping, reaming, etc., as well asfor various unrelated operations such as tube spinning and tubeexpanding. In ordinary circumstances not more than about two square feetof bench space are required and, unless otherwise desired, only fourbolts art the foulv corners of the base are necessary to hold inposition.

It is intended that the patent shall cover, by summarization in appendedclaims, all of the various features of patentable novelty that reside inthe invention.

What is claimed is:

1. A precision vise oi' the double-acting type comprising an elongatedbase; two opposed fluid pressure motors on said base, one at each endthereof, with their axes of reciprocation disposed above the top portionof the base, parallel to the axis of the base, and in alignment witheach other; opposed jaws mechanically connected to the two motors, oneto each thereof, in suoli manner that simultaneous movement of themotors simultaneously urges the jaws toward or from each other;depending portions on said jaws formed integrally with the jawsthemselves, said depending portions projecting downward below the bottomof the top portion of the base; and, between the depending portions ofthe jaws, means for synchronizing movement of the jaws, said meanscomprising two oppositely projecting racks carried by the dependingportions of the jaws the ends of which racks are guided by rackguidingsurfaces on the base and an intervening gear on the bottom face of thetop portion of the base which gear cooperates with the racks tosynchronize the movement of the jaws.

2. A precision vise oi the double-acting type comprising an elongatedbase that is slotted lengthwise of the base on each side of itslongitudinal axis; two opposed reciprocatory motors Lil) on said base,one at each end thereof, with their axes of reciprocation disposed abovethe top portion of the base, parallel to the axis of the base, and inalignment with each other, opposed jaws mechanically connected to thetwo motors, one to each thereof, in such manner that simultaneousmovement of the motors simultaneously urges the jaws toward or from eachother; depending portions on the jaws projecting downward below thebottom of the top portion of the base, said depending portions carryingoppositely projecting racks parts of which are in contact .withrack-guiding surfaces on the base; a gear intervening between andcooperating with the racks to synchronize the movement of the jaws, saidgear being mounted for rotation about a vertical axis below the bottomof the top portion of the base; guideways on the bottom of the topportion of the base; and, projecting downward from the two jaws throughthe slots in the base, a plurality of guide members each of which coactswith at least one of the guideways.

3. A precision vise as in claim 2 in which the motors are fluidepressure motors.

4.-. A precision vise as in claim 3 in which the fluid pressure motorstake the form of power cylinders.

5. A precision vise of the double-acting type comprising an elongatedbase; two opposed fluid pressure motors on said base, one at each endthereof, with their axes of reciprocation disposed above the top portionof the base, parallel to the axis of the base, and in alignment witheach other; opposed jaws mechanically connected to the two fluidpressure motors, one to each thereof, in such manner that simultaneousmovement of the motors simultaneously urges the jaws toward or from eachother; depending portions on the jaws projecting downward below thebottom of the top portion of the base, said depending portions carryingoppositely projecting racks parts of which are in contact withrack-guiding surfaces on the base; a gear intervening between andcooperating with the racks to synohronize the movement of the jaws, saidgear being mounted for rotation about a vertical axis below the bottomof the top portion of the base; fluid pressure lines connecting the nearends of the motors with each other and connecting the far ends of themotors with each other; and, at opposite ends of one of the motors,connections for admitting and exhausting pressure fluid,

6. A precision vise as in claim 5 in which the fluid pressure lines arelocated within the base itself below the bottom of the top portion ofthe base.

7. A precision vise as in claim 6 in which the fluid pressure linescrossimmediately below the gear in the central zone of the vise.

8. A precision vise of the double-acting type comprising an elongatedbase; two opposed fluid pressure motors on said base, one at each endthereof, with their axes of reciprocation disposed above the top portionof the base, parallel to the axis of the base, and in alignment witheach other; opposed jaws mechanically connected to the two motors, oneto each thereof, in such manner that reciprocatory movement of themotors urges the jaws toward or from each other; depending portions onthe jaws projecting downward below the bottom of the top portion of thebase, said depending portions carrying oppositely projecting racks partsof which are in contact with rack-guiding surfaces on the base; a gearintervening between and cooperating with the racks to synchronize themovement of the jaws, said gear being mounted for rotation about avertical axis below the bottom of the top portion of the base; guidewayson the bottom of the top portion of the base; and, coacting with saidguideways, guide means projecting downward from the two jaws intoproximity to said guideways.

9. A precision vise of the double-acting type comprising an elongatedbase that is slotted lengthwise of the base on each side of itslongitudinal axis; two opposed fluid pressure motors on said base, oneat each end thereof, with their axes of reciprocation disposed above thetop portion of the base, parallel to the axis of the base, and inalignment with each other; opposed jaws mechanically connected to thetwo motors, one to each thereof, in such manner that simultaneousmovement of vthe motors simultaneously urges the jaws toward or fromeach other; depending portions on the jaws projecting downward below thebottom of the top portion of the base, said depending portions carryingoppositely projecting racks parts of which are in Contact withrack-guiding surfaces on the base; a gear intervening between andcooperating with the racks to synchronize the movement of the jaws, saidgear being mounted for rotation about a Vertical aXis below the bottomof the top portion of the base; double guideways anking the slots on thebottom of the top portion of the base; and, projecting downward fromeach of the two jaws through the slots in the base, a plurality ofinverted T-shaped guide members, each of which fao-acts with one of thedouble guideways.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 2,253,713 Lancaster Aug. 26, 1941 2,289,597 Seat July 14, 19422,308,099 Obecny Jan. 12, 1943 2,448,478 White Aug. 31, 1948

